配电网中计及短路电流约束的分布式发电规划

Planning for Distributed Generation in Distribution Network with Short-circuit Current Constraints

在配电网中合理规划分布式发电(DG)对充分发挥DG的效益、抑制DG的负面影响具有重要意义。文中研究了配电系统中DG位置和容量规划问题,建立了考虑经济性和安全性的DG规划多目标模糊优化模型。目标函数由DG投资成本最小、系统网损最小和静态电压稳定裕度最大3个优化子目标组成,应用模糊理论将多目标规划转化为单目标规划问题。在模型中计及了短路电流约束,对配电网中计及DG影响的故障计算原理进行了分析。考虑到DG出力具有一定的间歇特点,模型中增加了系统的旋转备用约束,保证任意一台DG退出时。系统具有足够的功率来满足负荷要求。在43节点配电系统中进行了测试．表明了文中方法的可行性。

A rational planning scheme for distributed generation （DG） in the distribution network is of great significance for bringing the benefits of DG into full play and restraining the negative effects brought by DG. The sitting and sizing problems of DG in distribution systems are investigated and a multi-objective fuzzy optimal model is proposed that takes into account minimizing the investment cost of DG and the power loss of distribution network and maximizing the static voltage stability margin. The multi-objective planning is transformed into single objective planning by employing the fuzzy optimization theory. （）wing to an increase of the short-circuit current level （SCL） due to DG, the maximum SCL limit is taken into account in the constraints. The fault calculation principle in the distribution network with DG is analyzed. As DG has the intermission characteristic, a spinning reserve constraint is included in the model, that is, the distribution substation can supply sufficient power to meet load demands should any DG unit quit. The feasibility of the method proposed is shown by an example of a 43- bus distribution system.